Automatic drain device



y 2, 1933. M. P. KUDOLLA 1,907,299

AUTOMATIC DRAIN DEVICE Filed March 21. 1932 2 Sheets-Sheet 1 May 2, 1933. M. P. KUDOLLA AUTOMATIC DRAIN DEVICE Filed March 21, 1932 2 Sheets- Sheet 2 6556 s an. m W W. fiw

Patented May 2. 1933 UNITED STATES MILTON P. KUDOLLA, OF CHICAGO, ILLINOIS AUTOMATIC- nmm DEVICE Application filed March 21, 1932. Serial No. 600,356.

This invention relates to automatic drain devices, and has more particularly to do with the drainage of moisture from air and gas storage tanks and the like, the principal I object being to prevent the accumulation of water of condensation or from other causes. A more specific object is to produce a simple and efiicient device which may be readily applied to a tank in place of drain cock or valve, and which tomatically and without any loss of volume or pressure of the air or gas within the tank. Other objects and advantages to be attained Will hereinafter more fully appear.

The invention consists in the general application of the automatic drain device 'to pressure tanks, and in the parts and combinations and arrangements of parts as hereinafter described and pointed out with particularity in the appended claims.

In the accompanying drawings, forming part of this specification, and illustrating a practical adaptation of the invention,

Fig. 1 is a view, in side elevation, illusoperates auappreciable trating an arrangement of apparatus includin a pressure tank with the drain device the present invention applied, said tank having associated therewith an ordi nary motor driven air compressor, together with pressure controlled means for automatically starting and stopping the motor,

all of said parts being-shown more or less conventionally;

Fig. 2 is a fragmentary section, on an enlarged scale, illustrating details of the automatic drain device in one of its operative conditions;

' Fig. 3 is a similar view showing the relation of parts under different operative conditions; and

Fig. 4 is a transverse section, taken on or about the line 44 of Fig. 3.

Referring now to the drawings, the numeral designates an ordinary .storage tank for compressed air or a gaseous ele ment under pressure, said tank, as shown, being mounted on a base frame 11, on which is also mounted an ordinary air com ressor t The compressor 12 1S connecte by a said pressure creating the ordinary .quite obvious,

pipe 13 to said tank 10 and, as shown, is operably connected by a'belt 14 to the driving shaft 15 of an electric motor 16. Obviously, however, the invention is not limited to any particular type of tank nor pressure creating machine, or method of driving 7 machine, it being understood that pressure for operating purposes is maintalned between given minimum and maximum pressures within the storage 5" tank, which pressure is automatically controlled and regulated whereby the pressure creating machine or device is automatically brought into and out of action upon variation of the pressure within the a-certain predetermined degree.

For purposes of illustrating an embodimentof' the invention, the motor 16 is started and stopped through the intermediary of a switch 17 which latter is conventionally shown as provided with terminal contact members 18, 19, connected in the electrical supply circuit of the motor, and a movable contact 20 for connecting said terminal contact members 18 and 19, said movable contact member being carried by a bell crank 21, which :latter is inturn operatively connected, as at 22, with a plunger 23 operating in a pressure regulating casing 24. The foregoing parts are merely shown conventionally, as their operation is interior arrangements of the ressure control device 24 are" such that w en the pressure in the tank increases to a certain degree \95 the switch-17 is opened, thereby breaking the circuit and stopping the motor 16 and operation of the compressor 12, and upon decrease in pressure to a certain degree the switch 17 is closed and the motor and compressor are operated, this intermittent action occurring as the compressed air or gaseous element is drawn from the storage tank in the course of the operation of the usual working devices supplied therefrom. In this connection it is preferable to provide the storage tank 10 with'a pressure gauge or indicator 25 of any approved and efficient,

tank beyond 65 it being understood that the ype. a At the bottom of the storagetank' 10 i placed the automatic drain device of the present invention. In the embodiment illustrated, the device comprises a main body portion 26, preferably tapered or frustrr conical and inverted, the base portion having an. annular collar 27 which is externally screw-threaded "for the attachment thereto of the internally screw-threaded annular flange portion 28 of a supporting plate or member 29, said portion 29 having an axial nipple extension 30 externally screwthreaded, as at 31, to fit in the threaded hole usually provided in the bottom wall of v the tank 10 for the reception of the ordinary drain cocks which the device of the present invention is designed to replace.

The upper portion of the tapered or conical body 26. of the device, as shown, is internally bored cylindrically, as at 32, and fitted to reciprocate in said bore 32 is a piston 33 which, in most cases, will be a flat block with a plain cylindrical.circumferential face, although, obviously, it may be of any other approved. structure and provided with circumferential packin rings, if necessary. As shown, the piston is provided with a downwardly extending axial stem 34 which works loosely through an opening 35 in the bottom wall 36 of the body member 26 and extends some distance beyond said end wall 36, the end portion of the stem being screwt-hreaded, as at 37, for the reception of jam nuts 38 which afford an adjustable stop for variably limiting the upward movement of the piston 33. Coiled about the axial stem 34, and interposed between the piston 33 and the inner side of the end wall 36, is a helical spring 39, under compression at all times,

and of a strength sufficient to ton 33 in the cylindrical bore compressed air or, gaseous contents of the tank under a givcnpressure, at which time the upper jam nut 38 will be in contact with the end wall 36 of the body member 26 of the device, as shown in Fig. 3 of the drawings. However, when the pressure in the storage tank. 10 is increased to a degree above that at which the spring 39 is effective in raising the piston 33, as just above stated, the piston is forced downwardly by within the tank 10, the downward movement being'limited by a collar 40 whichengages the inner side of the bottom wall 36 of the body member 26, as shown in Fig. 20f the drawings. It may be here noted that the opening 35 is provided merely for guiding the axial stem 34 of the piston so as to prevent undue canting of the piston and, therefore, said opening 35 may be considerably larger in diameter than the stem 34, thereby permitting free longitudinal sliding movement of the screw-threaded. portion 37 of the shank through said opening.

raise the pis- Withinthe working range of the piston 33, the body portion 26 of the device is pro- 32 against the.

ture, for in operation,

the pressure vided with an annular chamber 41, said chamber being closed from communication with the cylindrical bore 32 in which the piston 33 operates, except where diametrically opposed upper horizontal slots 42 and correspondingly opposed lower longitudinal slots 43 are provided. lVhen the pressure in the storage tank 10 is suilicicnt to depress the piston 33 against the tension of the spring 39, as shown in Fig. 2 of the drawings, the upper slotted openings 42 are uncovered so that communication is cstablished between the bore 32 and said annular chamber 41, at which time the lower slotted openings 43are closed by the piston. hen the piston 33 is in this position and relation to the openings 42 and 43, any moisture or water of condensation which has accumulated in the storage tank 10 drains through the axial bore 44 of the nipple extension 30, into the cylindrical bore 32 above the piston 33 and thence into the annular chamber 41 through the upper slotted openings 42.

As soon as the pressure in the storage tank 10 decreases sufhciently to permit the spring 39 to react and move the piston 33 upwardly, thereby closing the upper slotted openings 42 and uncovering the lower slotted openings 43, the liquid which has been received in the annular chamber 41 drains therefrom through said lower slotted openings 43 into the lower chamber 45 of the body member 26, whence it is discharged through a series "movements of the piston 33 occur, the one pair'of the slots 42 or 43 are closed before the other pair are openedto communication with the cylindrical bore 32, the thickness In this of the piston taking care of-this., way loss or wastage of air from the storage tank 10 is practically avoided. I

By the provision of an automatic drain device in accordance with the present invention, the storagetank is kept free of moisthe device is intermittently actuated at frequent intervals, due to the fact that a constant given pressure is not maintained in the storage tank during operation of tools or working devices supplied therefrom; the compressor being actuated intermittently to increase'the pressure in the tank when the ressure has fallen to a certain degree, say, or example, when the pressure decreases ten or fifteen pounds below the maximum pressure required to operate the pressure controlled device which automatically effects the starting and stop- I ping of the compressor.

Obviously, the structure of the device admits of considerable modification without in the least departing from the spirit and scope of the invention as defined by the appended claims. The invention, therefore, is not limposite side of the piston,

itcd to the specific construction and arrangement shown.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An automatic drain device for fluid pressure tanks, said device comprising a casing having provision for communicable drainage attachment to the tank, said casing having a piston chamber in communication with said tank, a discharge chamher, a drainage receiving chamber interposed between said piston chamber and said discharge chamber, said drainage receiving chamber having an inlet opening communicable with said piston chamber and an outlet opening communicable with said discharge chamber, a piston in said piston chamber adapted in reciprocation to alternately close communication between said piston chamber andsaid drainage receiving between said drainage receiving chamber and said discharge chamber, said piston being automatically moved to and yieldably held in closing relation between said drainage receiving chamber and said discharge chamber under a given pressure from said tank, and means for automatically moving said piston to and yieldably holding it in closing relation between said drainage receiving and piston chambers upon decrease of pressure in said tank.

2. The combination of a pressure storage tank, and a drain device comprising a chambered body having a communicable nipple connection with the bottom of said tank, a reciprocatory piston working in a cylindrical bore of said chambered body, whereby to receive the pressure at one side of the piston, a continuation of said cylindrical bore constituting a discharge chamber, and

an annular chamber having an opening communicable with said cylindrical bore at one side of the piston and an opening communicable with said discharge chamber at the opsaid piston being adapted to alternately cover and uncover said openings, and a spring element acting to move said piston in the direction to close the communicable opening between said annular chamber and said cylindrical bore and uncovering the communicable opening be tween said annular chamber and said discharge chamber when the pressure in said tank is at a given degree, said piston being moved reversely against the tension of said spring element when the pressure in the tank increases to a given degree.

3. A11v automatic drain device for compressed air storage tanks and the like. said device comprising a casing having provision for communicable drainage attachment to the tank, said casing having a piston chamber, a discharge chamber, and an interchamber and upper portion ed in reciprocation to alternately close said upper and lower communicable openings between said intermediate drainage receiving chamber and said piston chamber and said discharge chamber, said piston being moved under given pressure from the storage tank to close the communicable opening between said, intermediate drainage receiving chamber and said discharge chamber, and aspring element for moving said piston reversely to close the communicable opening betweenintermediate drainage receiving chamber and said piston chamber upon decrease of pressure in the storage tank.

4. An automatic drain device comprising a chambered body having provision for communicable drainage attachment to a compressed air storage tank or the like, the

of said body being formed with a, cylindrical bore communicable with portion of said cylindrical bore merging into a discharge chamber, a reciprocatory piston workably fitted in said cylindrical bore and separating the latter from said discharge chamber, anannular intermediate drainage receiving chamber in the region of the working rangeof said piston, said cylindrical bore having provision for direct communication with the upper portion of said intermediate chamber, and said discharge chamber having similar provision for communication with the lower portion of said intermediate chamber, said piston in its reciprocation adapted to alternately close the upper and lower communicable openings between said intermediate chamber and said cylindrical bore and said discharge chamber, said piston being moved in the direction to thedrainage attachment means, the lower close communication between said intermediate chamber and said discharge chamber under given tank pressure, and means for moving said piston in the opposite direction to close communication betweensaid inter-- mediate chamber and said cylindrical bore upon decrease of pressure in the storage tank.

1 5. An automatic moisture drain device for compressed air storage tanks and the like, said device comprising an annularly flanged supportingmember having a bored nipple extension for communicable attachment to the tank, a body member having an annular collar portion at its upper end for detachable leak-tight engagement with said supporting member, said body member having a cylindrical bore in its upper portion, a discharge chamber in its lower portion, said cylindrical bore and discharge chamber merging" communicably, an annular intermediate chamber surrounding said cylindrical bore, said annular chamber communicating at top and bottom with said cylindrical bore through upper and lower horizontally slotted openings, said body member having a drain outlet at its bottom communicable with said dischar e chamber, a reciprocatorypiston worka ly fitted in said cy indrical bore of said body member, the cooperating peripheral portion of said piston alternately opening and closing said upper vand lower slotted communicable o en-- lugs between said annular int-erme iate chamber and 'said cylindrical bore during the reciprocation of said piston, said cooperating peri heral portion of the iston be- 4 ing of a wi th to close both of said slotted communicable openings prior to the opening of the one or the other of said openings,

and a spring element acting to move said piston in the direction to close the upper communicable opening between said annular intermediate chamber and-said cylindrical bore against a given tank pressure, said piston being moved in the opposlte direction to close the lower communicable opening between said annular intermediate chamber and said cylindrical bore upon increase of pressure 1n the tank suflicient to counteract said spring element.

In testimony whereof I have signed my I name to this s ecification.

TON P. KUDOLLA.

moaned 

